In the process of forming a glass lift-off mask on an underlay surface, the glass resin is often deposited over a photoresist made up of a solvent soluble polymer, specifically an organic layer. As the resin glass is spun onto the underlay surface, it has a tendency to polymerize. The polymerization occurs in a three-dimensional mode resulting in a unevenly distributed resin glass layer. If subsequent processing requires a step of etching the glass mask, the glass inclusions caused by the three-dimenisonal polymerization may not etch thoroughly and the glass which remains may present obstacles to subsequent processing, particularly if there is a need for a subsequently deposited layer to be planar and/or continuous. In the past, in order to eliminate the polymerization of glass resin, various extensive filtration techniques, such as filtering the glass through celite beds, have been utilized in efforts to "purify" the resin glass. Such attempts to prevent or modify the polymerization by treating the glass have proved unsuccessful; because, as herein disclosed, it has been determined that most of the polymerization takes place on the underlay surface itself, therefore requiring surface modification. Surface modification, in general, is not a new concept. Well-known teachings show surface modification to attain various ends, including increased adherence, better conductivity, improved dyeability and other ends (See: U.S. Pat. No. 3,829,324 and discussions therein).
It is therefore an objective of the present invention to provide a method for modifying an underlay surface in order to control the polymerization of subsequently deposited resin glass.
It is another objective of the invention to teach a method for providing an evenly distributed glass overlay surface.
It is a further objective of the invention to provide a means for avoiding metal opens in glass liftoff/metallization processing.